from launch import LaunchDescription
from launch_ros.actions import Node

def generate_launch_description():
    ld=LaunchDescription()
    sub_node=Node(
        package='topic_01',
        executable='subscriper_once_data_node_exec',
        name='subscriber_once_data_node',
        output='screen'
    )
    ld.add_action(sub_node)
    return ld